CN107851578B

CN107851578B - Reaction tube, substrate processing apparatus, and manufacturing method of semiconductor device

Info

Publication number: CN107851578B
Application number: CN201580081860.5A
Authority: CN
Inventors: 吉田秀成; 谷山智志; 中田高行
Original assignee: Kokusai Electric Corp
Current assignee: INTERNATIONAL ELECTRIC CO Ltd
Priority date: 2015-09-04
Filing date: 2015-09-04
Publication date: 2021-10-01
Anticipated expiration: 2035-09-04
Also published as: KR102138985B1; US20200240019A1; US10689758B2; US11155920B2; KR20180021194A; WO2017037937A1; CN107851578A; JPWO2017037937A1; US20180187307A1; KR102241665B1; KR20200090962A

Abstract

Provides a technique that can purge thermally insulated areas without adversely affecting the processing area. having a processing chamber inside, the processing chamber including a processing area for processing a substrate and a thermal insulation area located below the processing area, and having a first exhaust part for exhausting the atmosphere of the processing area; and a second exhaust portion formed at a position overlapping the heat insulating region in the height direction, and exhausting the atmosphere of the heat insulating region.

Description

Reaction tube, substrate processing apparatus, and method for manufacturing semiconductor device

Technical Field

The invention relates to a reaction tube, a substrate processing apparatus and a method for manufacturing a semiconductor device.

Background

In a heat treatment of a substrate in a manufacturing process of a semiconductor Device (Device), for example, a vertical substrate processing apparatus is used. In a vertical substrate processing apparatus, a predetermined number of substrates are aligned in a vertical direction and held by a substrate holder, the substrate holder is loaded into a processing chamber, and a processing gas is introduced into the processing chamber while the substrates are heated by a side heater provided outside the processing chamber, thereby performing a thin film forming process or the like on the substrates.

Disclosure of Invention

Problems to be solved by the invention

In the vertical substrate processing apparatus as described above, there are cases where: the purge gas for purging the heat insulating region flows into the process region of the process substrate, and the process gas is diluted, thereby adversely affecting the uniformity of the film formation.

An object of the present invention is to provide a technique capable of purging a heat insulating region without adversely affecting a processing region.

Means for solving the problems

According to one aspect of the present invention, there is provided a technique including a process chamber having a process region where a substrate is processed and an insulating region located below the process region, the technique including:

a first exhaust section that exhausts an atmosphere of the processing region, an

And a second exhaust unit formed at a position overlapping the heat insulating region in the height direction and configured to exhaust the atmosphere in the heat insulating region.

Effects of the invention

The present invention can provide a technique that can purge a heat insulating region without adversely affecting a processing region.

Drawings

Fig. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in the embodiment of the present invention, and is a diagram showing a vertical sectional view of a part of the processing furnace.

Fig. 2 is a block diagram for explaining a configuration of a control section of a substrate processing apparatus suitably used in the embodiment of the present invention.

Fig. 3 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in the second embodiment of the present invention, and is a diagram showing a vertical sectional view of a part of the processing furnace.

Fig. 4 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in the third embodiment of the present invention, and is a diagram showing a vertical sectional view of a part of the processing furnace.

Fig. 5 is a perspective view of a heat insulating part of a vertical processing furnace of a substrate processing apparatus suitably used in the third embodiment of the present invention.

Fig. 6 is a perspective view of an exhaust part (exhaust port) of a vertical processing furnace of a substrate processing apparatus suitably used in the embodiment of the present invention.

Fig. 7 is an explanatory view showing the mole fractions of the process gases in the vertical processing furnace of the substrate processing apparatus according to the third embodiment of the present invention and in the processing furnace of the comparative example.

FIG. 8 is a vertical sectional view showing the periphery of a heat insulating part of a vertical processing furnace of a substrate processing apparatus suitably used in the fourth embodiment of the present invention.

Detailed Description

Hereinafter, an embodiment of the present invention will be described with reference to fig. 1.

As shown in fig. 1, in the present embodiment, the substrate processing apparatus is configured as a vertical heat treatment apparatus (batch type vertical heat treatment apparatus) 10 that performs a heat treatment process in the IC manufacturing method.

The processing furnace 12 includes a heater 14 which is a heater unit (hereinafter, referred to as a heater) as a first heating member (heating means). The heater 14 is cylindrical and supported by a heater base 16 as a holding plate to be vertically installed. As described later, the heater 14 functions as an activation mechanism (excitation portion) that activates (excites) a gas by heat.

Inside the heater 14, a reaction tube 18 constituting a reaction vessel (processing vessel) is disposed. The reaction tube 18 is made of, for example, quartz (SiO)₂) Or a heat-resistant material such as silicon carbide (SiC), and is formed in a cylindrical shape with its upper end closed and its lower end open. The reaction tube 18 and the heater 14 are arranged concentrically. The outer wall of the reaction tube 18 has a gas supply space 24A as a supply buffer chamber and a gas exhaust space 24B as an exhaust buffer chamber facing each other, and these spaces are formed so as to protrude outward of the reaction tube 18. The gas supply space 24A is formed by the outer wall of the reaction tube 18 and the partition 18A. The gas exhaust space 24B is formed by the outer wall of the reaction tube 18 and the partition 18B. The

partitions

18A and 18B are formed as part of the side walls (inner walls) of the reaction tubes 18. A flange 18C projecting outward is formed at the lower end of the partition 18B. The lower end of the reaction tube 18 is supported by a metal header 22.

A treatment chamber 24 is formed in the hollow portion of the reaction tube 18. The process chamber 24 is configured to accommodate wafers W as substrates in a state of being arranged in a plurality of stages in a vertical direction in a horizontal posture by a wafer boat 26 described later. The processing chamber 24 includes a processing region a and a heat insulating region B described later.

In the gas supply space 24A, a nozzle 28 is provided. The nozzle 28 is made of a heat-resistant material such as quartz or SiC. The nozzle 28 is connected to a gas supply pipe 30 a. A Mass Flow Controller (MFC)32a as a flow controller (flow rate control unit) and a valve 34a as an on-off valve are provided in this order from the upstream side in the gas supply pipe 30 a. A gas supply pipe 30b for supplying an inert gas is connected to the downstream side of the valve 34a of the gas supply pipe 30 a. The gas supply pipe 30b is provided with an MFC32b and a valve 34b in this order from the upstream side. The gas supply pipe 30a, the MFC32a, and the valve 34a mainly constitute a process gas supply unit as a process gas supply system. The gas supply pipe 30b, the MFC32b, and the valve 34b constitute an inert gas supply unit as an inert gas supply system. It is also conceivable to include the gas supply pipe 30b, the MFC32b, and the valve 34b in the process gas supply unit (process gas supply system).

The nozzle 28 is provided so as to stand upward in the arrangement direction of the wafers W in the gas supply space 24A from the lower portion to the upper portion of the reaction tube 18. That is, the nozzle 28 is provided along the wafer arrangement region in a region horizontally surrounding the wafer arrangement region on the side of the wafer arrangement region where the wafers W are arranged. The nozzle 28 is formed as an L-shaped extended nozzle, and a horizontal portion thereof is provided to penetrate through a side wall of the manifold 22. In addition, the vertical portion is provided to stand at least from one end side toward the other end side of the wafer arrangement region. A gas supply hole 28A for supplying gas is provided in a side surface of the nozzle 28. The gas supply holes 28A are opened toward the center of the reaction tube 18, and can supply gas toward the wafer W. The gas supply holes 28A are provided in a plurality in a region where a substrate is processed (a wafer W placement region of the wafer boat 26, hereinafter referred to as a processing region a) in a range from a lower portion to an upper portion of the reaction tube 18. The gas supply holes 28A have the same opening area, respectively, and are arranged at the same opening pitch.

In the partition portion 18A, a plurality of gas supply slits 36A in the form of laterally long slits are provided in a range from the lower portion to the upper portion of the processing region a of the partition portion 18A so as to correspond to the gas supply holes 28A.

As shown in fig. 6, in the partition 18B, a plurality of gas exhaust slits 36B in the form of laterally long slits as first exhaust portions (first exhaust ports) are provided in a range from the lower portion to the upper portion of the processing region a of the partition 18B. The gas exhaust slit 36B is formed of a plurality of rows of openings having substantially the same width as the gas exhaust space 24B, and is provided at a position overlapping the processing region a in the height direction. The gas exhaust slit 36B is provided at a position corresponding to the gas supply slit 36A (a position facing the processing region a, i.e., a position facing the processing region a). The gas exhaust slit 36B is formed to communicate the process chamber 24 with the gas exhaust space 24B, and exhausts the atmosphere of the process field a in the process chamber 24.

An exhaust port 62 as a second exhaust portion (second exhaust port) is formed below the gas exhaust slit 36B of the partition portion 18B. The exhaust port 62 is formed at a position overlapping with a region below the processing region a (a region including the heat insulating portion 54, hereinafter referred to as a heat insulating region B.) in the height direction. In other words, the exhaust port 62 is formed at a position corresponding to the heat insulating region B, that is, a position facing the heat insulating region B. That is, the exhaust port 62 may be formed at a position facing the heat insulating region B. The exhaust port 62 is formed in a rectangular shape, and has an opening area larger than one opening area of the gas exhaust slit 36B and smaller than the total opening area of the gas exhaust slit 36B. The width of the long side of the rectangle of the exhaust port 62 is set to be equal to or less than the width of the gas exhaust space 24B. With such a configuration, particularly at the boundary portion between the process field a and the heat insulating field B, the purge gas can be suppressed from being exhausted from the gas exhaust slit 36B, and deterioration in film formation uniformity due to the purge gas reaching the process field a, which is the film formation region, can be suppressed. The exhaust port 62 is formed to communicate the process chamber 24 with the gas exhaust space 24B, and exhausts the atmosphere in the heat insulating region B in the process chamber 24. That is, by providing the exhaust port 62 in the heat insulating region B, the purge gas flowing around the heat insulating portion 54 can be prevented from diffusing into the process field a, and the process gas in the process field a can be prevented from being diluted to deteriorate the film formation uniformity.

At the lower end of the reaction tube 18, an exhaust port 19 communicating with the gas exhaust space 24B is provided. An exhaust pipe 38 for exhausting the atmosphere in the processing chamber 24 is connected to the exhaust port 19. A vacuum pump 44 as a vacuum exhaust device is connected to the exhaust pipe 38 via a Pressure sensor 40 as a Pressure detector (Pressure detecting unit) for detecting the Pressure in the processing chamber 24 and an apc (auto Pressure controller) valve 42 as a Pressure regulator (Pressure adjusting unit). The APC valve 42 can perform vacuum exhaust and vacuum exhaust stop in the processing chamber 24 by opening and closing the valve in a state where the vacuum pump 44 is operated, and the APC valve 42 is configured as follows: the pressure in the processing chamber 24 can be adjusted by adjusting the valve opening degree based on the pressure information detected by the pressure sensor 40 in a state where the vacuum pump 44 is operated. The exhaust system is mainly constituted by the exhaust pipe 38, the APC valve 42, and the pressure sensor 40. It is also contemplated that the vacuum pump 44 may be included in the exhaust system.

The position of the exhaust port 62 is preferably formed at a position overlapping the heat insulating portion 54 in the height direction. Further preferably, the metal oxide is formed at the following positions: the opening area of the exhaust port 62 is at least partially overlapped with the opening area of the exhaust port 19 (exhaust pipe 38) in the horizontal direction. By configuring in this way, the purge gas can be exhausted more efficiently. Further, the process gas and the purge gas can be smoothly exhausted without stagnation or stagnation of the process gas and the purge gas in the gas exhaust space 24B.

A seal cap 46 as a furnace opening lid body that can hermetically seal the lower end opening of the header 22 is provided below the header 22. The seal cap 46 is made of metal such as stainless steel or Ni alloy, and is formed in a disk shape. An O-ring 48 as a sealing member is provided on the upper surface of the seal cap 46 to be in contact with the lower end of the header 22. Further, a seal cover plate 50 for protecting the seal cap 46 is provided on the upper surface of the seal cap 46 in an inner region inside the O-ring 48. The sealing cover 50 is made of a heat-resistant material such as quartz or SiC, and is formed in a disk shape.

The sealing cap 46 is configured to abut against the lower end of the manifold 22 from the vertically lower side, and is configured to be vertically lifted by a boat lifter 52 as a lifting mechanism provided vertically outside the reaction tube 18. That is, the boat elevator 52 is configured to be able to carry in and out the boat 26 into and out of the processing chamber 24 by elevating and lowering the seal cap 46. In other words, the boat elevator 52 is configured as a conveying device (conveying mechanism) that conveys the wafer boat 26, i.e., the wafers W, into and out of the processing chamber 24.

The wafer boat 26 as a substrate support is configured to support a plurality of wafers W (for example, 25 to 200 wafers W) in a vertical direction in a horizontal posture with their centers aligned with each other, and to support the wafers W in multiple stages, even if the wafers W are arranged at intervals. The boat 26 is made of a heat-resistant material such as quartz or SiC.

A heat insulating portion 54 is provided below the wafer boat 26. The heat insulating portion 54 is, for example, a quartz cover formed in a cylindrical shape. The quartz cover is not limited to a quartz cover, and a plurality of thermal shields formed in a disk shape may be supported in a horizontal posture in a multi-layer manner.

A temperature detector 56 as a temperature detector is provided along the outer wall of the reaction tube 18. The temperature inside the processing chamber 24 is set to a desired temperature distribution by adjusting the energization of the heater 14 based on the temperature information detected by the temperature detector 56.

A rotary shaft 60 for rotating the boat 26 is fixed to a lower portion of the heat shield 54. A rotation mechanism 58 for rotating the boat 26 is provided below the rotation shaft 60 and on the side of the seal cover 46 opposite to the process chamber 24.

The rotating mechanism 58 has a substantially cylindrical case 58A having an open upper end and a closed lower end. A gas supply pipe 30c is connected to the housing 58A. The gas supply pipe 30c is provided with an MFC32c and a valve 34c in this order from the upstream side. The gas supply pipe 30c, the MFC32c, and the valve 34c mainly constitute a purge gas supply unit as a purge gas supply system for supplying a purge gas to the heat insulating region B. The purge gas supply unit is configured to supply a purge gas from a position below the heat insulating region B toward an upper side. The purge gas is supplied from the gas supply pipe 30c through the casing 58A and the periphery of the rotary shaft 60 from a position below the heat insulating region B toward the upper side.

As shown in fig. 2, the controller 200 as a control Unit (control means) is configured as a computer including a CPU (Central Processing Unit) 212, a RAM (Random Access Memory) 214, a storage device 216, and an I/O port 218. The RAM124, the storage device 216, and the I/O port 218 are configured to be able to exchange data with the CPU212 via an internal bus 220. An input/output device 222 configured as a touch panel or the like, for example, is connected to the controller 200.

The storage device 216 is configured by, for example, a flash memory, an HDD (Hard Disk Drive), or the like. The storage device 216 stores a control program for controlling the operation of the substrate processing apparatus, a process recipe in which steps, conditions, and the like of substrate processing described later are described so as to be readable. The process steps are combined so that the controller 200 can execute each step in the substrate processing step described later to obtain a predetermined result, and function as a program. Hereinafter, the process, the control procedure, etc. will be collectively referred to as a procedure. In the present specification, when the term "program" is used, only a process may be included, only a control program may be included, or both may be included. The RAM214 is configured as a storage area (work area) for temporarily storing programs, data, and the like read by the CPU 212.

The I/O port 218 is connected to the

MFCs

32a, 32b, 32c,

valves

34a, 34b, 34c, pressure sensor 40, APC valve 42, vacuum pump 44, heater 14, temperature detection unit 56, rotation mechanism 58, boat elevator 52, and the like described above.

The CPU212 is configured to read out and execute a control program from the storage device 216, and read out a process recipe from the storage device 216 in accordance with input of an operation command from the input/output device 222, or the like. The CPU212 is configured to control flow rate adjustment operations of the respective gases of the

MFCs

32a, 32b, 32c, opening and closing operations of the

valves

34a, 34b, 34c, opening and closing operations of the APC valve 42, pressure adjustment operations of the APC valve 42 by the pressure sensor 40, start and stop of the vacuum pump 44, temperature adjustment operations of the heater 14 by the temperature detection unit 56, rotation and rotation speed adjustment operations of the boat 26 by the rotation mechanism 58, lifting and lowering operations of the boat 26 by the boat lifter 46, and the like, in accordance with the contents of the read process recipe.

The controller 200 can be configured by installing the above-described program stored in the external storage device 224 (for example, a magnetic disk such as a magnetic tape, a flexible disk, or a hard disk, an optical disk such as a CD or a DVD, an optical magnetic disk such as an MO, a USB memory, or a semiconductor memory such as a memory card) in a computer. The storage device 216 and the external storage device 224 are configured as computer-readable recording media. Hereinafter, they will be collectively referred to as simply "recording media". In the present specification, when the term recording medium is used, the storage device 216 may be included alone, the external storage device 224 may be included alone, or both of them may be included. Note that the program may be provided to the computer by using a communication means such as the internet or a dedicated line without using the external storage device 224.

Next, a description will be given of a sequence of a process of forming a film on a substrate (hereinafter, also referred to as a film forming process) as one step of a manufacturing process of a semiconductor Device (Device) by using the substrate processing apparatus 10. Here, an example will be described in which a film is formed on a wafer W as a substrate by alternately supplying a first process gas (source gas) and a second source gas (reaction gas) to the wafer W.

The use of hexachlorodisilane (Si) as the source gas is explained below₂Cl₆For short: HCDS) gas, ammonia (NH) as a reaction gas₃) Forming a silicon nitride film (Si) on the wafer W by using the gas₃N₄Film, hereinafter, also referred to as SiN film). In the following description, the operations of the respective units constituting the substrate processing apparatus 10 are controlled by the controller 200.

In the film formation process in the present embodiment, a cycle in which the following steps are performed non-simultaneously is performed a predetermined number of times (1 or more), thereby forming an SiN film on the wafer W:a step of supplying HCDS gas to the wafer W in the processing chamber 24, a step of removing HCDS gas (residual gas) from the processing chamber 24, and a step of supplying NH gas to the wafer W in the processing chamber 24₃Gas step, and NH removal from the process chamber 24₃And (4) gas (residual gas).

For convenience of the present specification, the above-described film formation procedure may be expressed as follows. In the following modifications and other embodiments, the same expressions are used.

In the present specification, the term "wafer" is used to refer to "wafer itself", "a laminate (aggregate) of a wafer and a predetermined layer, film, or the like formed on the surface of the wafer", that is, a wafer including a predetermined layer, film, or the like formed on the surface. In the present specification, the term "surface of a wafer" may be used to refer to a "surface (exposed surface) of the wafer itself" and to a "surface of a predetermined layer, film or the like formed on the wafer, that is, an outermost surface of the wafer as a laminate".

Therefore, in the present specification, the phrase "supplying a predetermined gas to a wafer" may mean "supplying a predetermined gas to a surface (exposed surface) of the wafer itself", and may mean "supplying a predetermined gas to a layer, a film, or the like formed on the wafer, that is, to the outermost surface of the wafer as a laminated body". In the present specification, the term "forming a predetermined layer (or film) on a wafer" may mean "forming a predetermined layer (or film) on the surface (exposed surface) of the wafer itself", and may mean "forming a predetermined layer (or film) on a layer, film, or the like formed on a wafer, that is, on the outermost surface of a wafer as a laminate".

In this specification, the term "substrate" is used synonymously with the term "wafer".

(wafer filling and boat loading)

After a plurality of wafers W are loaded (wafer loading) into the boat 26, the boat 26 is carried in (boat loading) into the processing chamber 24 by the boat elevator 52. At this time, the seal cap 46 is in a state of hermetically closing (sealing) the lower end of the header 22 via the O-ring 48. When the lower end of the manifold 22 is hermetically closed, the valve 34c is opened to start the supply of the purge gas to the heat shield region B. The purge gas supplied upward from the lower position of the heat insulating region B purges the heat insulating region B including the heat insulating portion 54 and the periphery of the heat insulating portion 54, and is discharged from the exhaust port 62. By maintaining the supply of the purge gas from below to above the heat insulating region B and exhausting the purge gas from the exhaust port 62 provided at the side facing the heat insulating region B, the purge gas supplied to the heat insulating region B can be suppressed from diffusing into the film formation region. In addition, the valve 34c may be opened to start supplying the purge gas to the heat insulating portion 54 from a standby state before filling the wafer. In this case, particles introduced from the outside during wafer filling can be prevented from adhering to the control section 54.

(pressure control and temperature control)

The processing chamber 24 is evacuated (depressurized) by the vacuum pump 44 so that a predetermined pressure (vacuum degree) is achieved therein. At this time, the pressure in the processing chamber 24 is measured by the pressure sensor 40, and the APC valve 42 is feedback-controlled based on the measured pressure information. The vacuum pump 44 is kept in operation until the process on the wafer W is completed.

The inside of the processing chamber 24 is heated by the heater 14 so that the wafer W in the processing chamber 24 has a predetermined temperature. At this time, the energization of the heater 14 is feedback-controlled based on the temperature information detected by the temperature detector 26 so that the processing chamber 24 has a predetermined temperature distribution. The heating in the processing chamber 24 by the heater 14 is continued at least until the end of the processing of the wafer W.

Further, the rotation mechanism 58 starts to rotate the boat 26 and the wafers W. The wafer boat 26 is rotated by the rotation mechanism 58 via the rotation shaft 60, and the wafers W are thereby rotated. The rotation of the wafer boat 26 and the wafers W by the rotation mechanism 58 is continued at least until the process on the wafers W is completed.

(film formation treatment)

If the temperature in the processing chamber 24 is stabilized at the predetermined processing temperature, the following 2 steps, i.e., steps 1 to 2, are sequentially performed.

[ step 1]

In this step, HCDS gas is supplied to the wafer W in the process chamber 24.

The valve 34a is opened, and HCDS gas is flowed into the gas supply pipe 30 a. The HCDS gas is supplied to the processing region a in the processing chamber 24 through the gas supply hole 28A of the nozzle 28, the gas supply space 24A, and the gas supply slit 36A, and is exhausted from the exhaust pipe 38 through the gas exhaust slit 36B and the gas exhaust space 24B, with the flow rate thereof being adjusted by the MFC32 a. At this time, the HCDS gas is supplied to the wafer W. At this time, the valve 34b is simultaneously opened, and N flows into the gas supply pipe 30b₂A gas. N is a radical of₂The gas is supplied to the processing region a in the processing chamber 24 together with the HCDS gas through the gas supply hole 28A of the nozzle 28, the gas supply space 24A, and the gas supply slit 36A by flow rate adjustment through the MFC32B, and is exhausted from the exhaust pipe 38 through the gas exhaust slit 36B and the gas exhaust space 24B. By supplying HCDS gas to the wafer W, a silicon (Si) -containing layer having a thickness of, for example, less than 1 atomic layer to several atomic layers is formed as a first layer on the outermost surface of the wafer W.

After the first layer is formed, the valve 34a is closed, and the supply of HCDS gas is stopped. At this time, the inside of the processing chamber 24 is evacuated by the vacuum pump 44 while keeping the APC valve 42 open, and the HCDS gas remaining in the processing chamber 24 after the unreacted or contributing to the formation of the first layer is exhausted from the processing chamber 24. At this time, the holding valve 34b is opened to maintain N₂Supply of gas into the process chamber 24. N is a radical of₂The gas functions as a purge gas, and thus, the effect of discharging the gas remaining in the process chamber 24 from the process chamber 24 can be improved.

At this time, the gas remaining in the process chamber 24 may not be completely exhausted, or the process chamber 24 may not be completely purged. If remaining in the processing chamber 24If the amount of the gas (2) is small, the gas (2) does not have an adverse effect in the step (2) to be performed later. For N supplied into the processing chamber 24₂The flow rate of the gas does not need to be a large flow rate, and for example, the gas is supplied with N in an amount equivalent to the volume of the reaction tube 18 (the processing chamber 24)₂The gas can be purged to such an extent that no adverse effect is caused in step 2. Thus, the inside of the processing chamber 24 is not completely purged, so that the purge time can be shortened and the productivity can be improved. Can also convert N to₂The consumption of gas is suppressed to the minimum required.

[ step 2]

After step 1 is completed, NH is supplied to the wafer W in the processing chamber 24, that is, the first layer formed on the wafer W₃A gas. NH (NH)₃The gas is activated by heat to supply the wafer W.

In this step, the opening and closing of the

valves

34a and 34b are controlled in the same manner as the opening and closing of the

valves

34a and 34b in step 1. NH (NH)₃The gas is supplied to the processing region a in the processing chamber 24 through the gas supply hole 28A of the nozzle 28, the gas supply space 24A, and the gas supply slit 36A, and is exhausted from the exhaust pipe 120 through the gas exhaust slit 36B and the gas exhaust space 24B, by flow rate adjustment of the gas through the MFC32 a. At this time, NH is supplied to the wafer W₃And (4) qi. NH supplied to wafer W₃The gas reacts with at least a portion of the first layer, i.e., the Si-containing layer, formed on the wafer W in step 1. Thereby, the first layer is thermally nitrided by non-plasma, and is changed to a silicon nitride layer (SiN layer) that is a second layer containing Si and N (modified). In this case, the NH excited by the plasma may be used₃The first layer is changed to a second layer (SiN layer) by supplying gas to the wafer W to plasma-nitridize the first layer.

After the second layer is formed, the valve 30a is closed, and NH is stopped₃And (4) supplying gas. At this time, the APC valve 42 is kept open, the inside of the processing chamber 24 is evacuated by the vacuum pump 44, and NH remaining in the processing chamber 24 after unreacted or contributing to the formation of the second layer₃Gas is exhausted from the process chamber 24. At this time, the holding valve 34b is opened to maintain N₂Gas directionThe supply in the treatment chamber 24. N is a radical of₂The gas functions as a purge gas, and thus the effect of discharging the gas remaining in the process chamber 24 from the process chamber 24 can be improved. In this case, the process is similar to step 1 in that the gas or the like remaining in the process chamber 24 is not completely exhausted.

(number of execution times)

By performing the cycle of performing the above 2 steps non-simultaneously, i.e., asynchronously, a predetermined number of times (n times), an SiN film having a predetermined composition and a predetermined film thickness can be formed on the wafer W. The above cycle is preferably repeated a plurality of times. That is, it is preferable that the thickness of the second layer (SiN layer) formed when the above-described cycle is performed 1 time is made smaller than the predetermined film thickness, and the above-described cycle is repeated a plurality of times until the film thickness of the SiN film formed by laminating the second layers (SiN layers) reaches the predetermined film thickness.

As the process conditions for performing the film formation process, for example, there can be exemplified:

process temperature (wafer temperature): at the temperature of 250-700 ℃,

process pressure (pressure in process chamber): the pressure of the liquid is 1 to 4000Pa,

HCDS gas supply flow rate: 100 to 200sccm of the flow-rate control liquid,

NH₃gas supply flow rate: 1000 to 20000sccm,

N₂gas (purge gas for purging heat insulation region B) supply flow rate: 0 to 500sccm of the metal oxide film,

N₂gas (purge gas for purging process field a) supply flow rate: 0 to 1000 sccm.

By setting each process condition to a certain value within each range, the film formation process can be appropriately performed. Preferably, the supply flow rate of the purge gas for purging the heat insulating region B is set to be equal to or less than the supply flow rate of the process gas.

(purge and atmospheric pressure recovery)

After the film formation process is completed, the valve 34b is opened to supply N from the gas supply pipe 30b to the process field A in the process chamber 24₂The gas is exhausted from the exhaust pipe 38 through the gas exhaust slit 36B, thereby removing the gas remaining in the processing chamber 24,Reaction by-products are removed (purged) from the process chamber 24. Thereafter, the atmosphere in the processing chamber 24 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 24 is returned to normal pressure (atmospheric pressure recovery).

(boat unloading and wafer taking out)

The seal cap 46 is lowered by the boat elevator 52 to open the lower end of the manifold 22. The processed wafers W are then carried out from the lower end of the manifold 22 to the outside of the reaction tube 18 (boat unloading) while being supported by the boat 26. The processed wafers W are taken out (wafer take-out) from the boat 26.

Next, a second embodiment will be explained. The second embodiment differs from the above embodiments in that a flange portion 18C at the lower end of the reaction tube 18 further includes a third exhaust portion (third exhaust port) for exhausting the atmosphere in the heat insulating region B. Hereinafter, the same reference numerals are given to the elements substantially the same as those described with reference to fig. 1, and the description thereof will be omitted.

As shown in fig. 3, an exhaust port 64 as a third exhaust portion (third exhaust port) is formed in the flange portion 18C of the reaction tube 18 below the exhaust port 62. The exhaust port 64 is formed so as to communicate with the gas exhaust space 24B below the process chamber 24. The purge gas supplied from the gas supply pipe 30c is discharged from the exhaust port 62 and the exhaust port 64, and the atmosphere in the heat-insulating region B is exhausted. That is, the purge gas supplied around the heat shield 54 can be prevented from diffusing into the film formation region, and deterioration in film formation uniformity due to dilution of the process gas in the film formation region can be prevented. Further, since the periphery of the furnace opening portion, which is a region of the heat insulating region B, particularly the periphery of the manifold 22, can be directly exhausted, the retention and stagnation of the purge gas in this region can be prevented.

The opening area of the exhaust port 64 is preferably formed smaller than the opening area of the exhaust port 62. Further, it is preferable that the lateral width of the exhaust port 64 is formed narrower than the lateral width of the exhaust port 62. With this configuration, the amount of exhaust gas from the exhaust port 62 can be made larger than the amount of exhaust gas from the exhaust port 64, and a large amount of purge gas can be prevented from being discharged from the exhaust port 64 before the purge gas reaches the heat insulating portion 54 and the periphery of the heat insulating portion 54, so that the heat insulating portion 54 can be appropriately purged.

Next, a third embodiment will be explained. In the third embodiment, the heat insulating portion 66 divided vertically is used, unlike the first embodiment.

As shown in fig. 4 and 5, the heat insulating portion 66 is divided into a cylindrical upper heat insulator 66A and a cylindrical lower heat insulator 66B. Around the upper surface of the lower insulator 66B, for example, 4 cylindrical support portions 68 are provided at equal intervals, and the upper insulator 66A is supported by the support portions 68 at a predetermined interval S from the lower insulator 66B.

The exhaust port 62 is formed at the following positions: the position of the exhaust port 62 in the height direction partially overlaps the space S between the upper insulator 66A and the lower insulator 66B. Thereby, the purge gas supplied to the periphery of the heat insulating portion 66 is exhausted to the exhaust port 62 through the space S between the upper heat insulator 66A and the lower heat insulator 66B. That is, the purge gas flowing through the narrow gap between the heat insulating portion 66 and the inner wall of the exhaust pipe 18 on the opposite side of the exhaust port 62 may be difficult to be exhausted and easily spread to the process field a because the exhaust port 62 is not located in the vicinity, but the purge gas may be more efficiently exhausted without reaching the process field a because the purge gas flows toward the space S by forming the space S. Preferably, the exhaust port 62 is formed at a position where at least a part of the opening of the exhaust port 62 and at least a part of the space S overlap in the height direction. By configuring in this way, the purge gas passing through the space S can be linearly exhausted through the exhaust port 62, and an exhaust gas flow without stagnation can be formed.

Fig. 7 shows the mole fractions of the process gases in the process area a and the insulating area B in the reaction tube 18 using the exhaust port 62 and the insulating portion 66 (having the structure with the space S) with intermediate exhaust gas according to the third embodiment, and the reaction tube 18 using the exhaust port 62 and the insulating portion without intermediate exhaust gas according to the comparative example. As shown in fig. 7, in the process field a in the reaction tube 18 in the comparative example, the purge gas purged from the heat insulating portion diffuses into the process field a and the process gas is diluted. In particular, in the heat insulating region B, the mole fraction of the process gas becomes small in the vicinity of the furnace opening portion of the reaction tube 18. In contrast, in the heat insulating portion 66 having the intermediate exhaust gas, the purge gas having passed through the interval S of the heat insulating portion 66 is exhausted from the exhaust port 62, so that the diffusion of the purge gas into the processing region a is suppressed, and the processing region a has substantially the same mole fraction over the entire region. That is, by dividing the heat insulating portion 66 into the spaces S and exhausting the purge gas from the exhaust port 62 through the spaces S, the purge gas passing through the heat insulating region B can be suppressed from diffusing into the process field a, and deterioration in film formation uniformity due to dilution of the process gas in the process field a can be suppressed.

In the third embodiment, the structure using the cylindrical upper insulator 66A and the cylindrical lower insulator 66B is described, but the present invention is not limited thereto, and the following structure may be adopted: the heat insulator has a structure in which a plurality of heat insulating plates are stacked, and a space S is provided between the stacked heat insulating plates so that the height position of the space S partially overlaps the exhaust port 62. In addition, not only the exhaust port 62 but also the exhaust port 64, which is the third exhaust portion (third exhaust port) described in detail in the second embodiment, may be provided.

Next, a fourth embodiment will be explained. In the fourth embodiment, the configuration of the heat insulating portion and the rotary shaft is different from that of the second embodiment, and a purge gas supply portion is provided inside the rotary shaft 72.

As shown in fig. 8, the heat insulating portion 70 includes a disc-shaped receiving portion 78, a holding portion 80 that holds the stacked heat insulators 74, and a cylindrical portion 82 that covers the stacked heat insulators 74. A holding portion 80 and a cylindrical portion 82 are fixed to the upper surface of the receiving portion 78.

The receiving portion 78 is formed of a metal such as stainless steel. The receiving portion 78 has a through hole formed at the center thereof. Further, the receiving portion 78 is formed with air discharge holes 78A for discharging air from the cylindrical portion 82 at predetermined intervals. The exhaust holes 78A are formed at equal intervals, for example, along a concentric circle of the receiving portion 78.

The holding portion 80 has a cylindrical through hole with an open lower end. The sub-heater 76, which is a heater unit (hereinafter referred to as a sub-heater) serving as a second heating member (heating means), is vertically inserted into the through-hole of the holding portion 80. The sub-heater 76 includes a support portion 76A extending vertically and a heat generating portion 76B connected horizontally to the support portion 76A. The heat generating portion 76B is provided in a region between the upper end of the support portion 76A and the inner wall of the cylindrical portion 82. This can suppress the radiant heat of the sub-heater 76 from escaping to the outside of the processing region a, and can shorten the temperature rise time. The heat generating portion 76B is formed in a substantially annular shape having a diameter smaller than the outer diameter of the wafer W, and is supported by the column portion 76A so as to be parallel to the wafer W. A heater bare wire, which is a resistance heating wire as a coil-shaped heating element, is sealed inside the heating portion 76B. The sub-heater 76 is disposed between the boat 26 and the heat insulator 74, and heats the wafers W (the processing region a) from below.

The holding portion 80 is provided with a reflection plate 74A and a heat insulating plate 74B as the heat insulator 74. The reflection plate 74A is fixedly held by welding, for example, at the upper portion of the holding portion 80. The heat shield plate 74B is fixedly held by, for example, welding at the intermediate portion of the holding portion 80.

The reflection plate 74A is formed in a circular plate shape having a diameter smaller than that of the wafer W, and is formed of, for example, opaque quartz. The thermal shield plate 74B is formed in a disk shape having an outer diameter smaller than the outer diameter of the wafer W, and is formed of a material having a small heat capacity, for example, quartz, silicon (Si), SiC, or the like.

A through hole is formed in the rotary shaft 72, and the support portion 76A of the sub-heater 76 is inserted through the through hole. A receiving portion 78 is fixed to an upper end portion of the rotary shaft 72.

That is, support portion 76A of sub-heater 76 is inserted into the through hole of rotary shaft 72, receiving portion 78, and holding portion 80.

The inner diameters of the through holes of the rotary shaft 72, the receiving portion 78, and the holding portion 80 are configured to be larger than the outer diameter of the supporting portion 76A of the sub-heater 76, and an annular space is formed between the inner walls of the rotary shaft 72, the receiving portion 78, and the holding portion 80, and the outer wall of the supporting portion 76A. A first flow path as a purge gas supply path for supplying a purge gas is formed in an annular space (around support portion 76A) between the inner walls of rotation shaft 72, receiving portion 78, and holding portion 80 and the outer wall of support portion 76A.

A gas supply pipe 30c is connected to the annular space. The gas supply pipe 30c is provided with an MFC32c and a valve 34c in this order from the upstream side. The upper end of the holding portion 80 is configured in the form of a supply port 80A. The supply port 80A is an annular opening, and the purge gas is supplied from the supply port 80A toward the inside and upper side of the cylindrical portion 82. By providing the supply port 80A as an annular opening, the purge gas can be uniformly supplied over the entire outer circumferential direction of the upper end of the cylindrical portion 82 and the annular flat surface.

The cylindrical portion 82 is formed in a cylindrical shape with a closed upper end to house the sub-heater 76 therein.

The upper end of the cylindrical portion 82 is formed in a convex shape. With such a configuration, the thickness of the top plate portion of the cylindrical portion 82 can be reduced, and the heating efficiency below the processing region a by the sub-heater 76 can be improved. Further, the flow of the gas in the cylindrical portion 82 can be improved, and the gas can be prevented from staying in the convex portion. Further, since the purge gas supplied from the supply port 80A flows from above to below along the side wall in the cylindrical portion 82 after colliding with the inner wall of the upper surface of the cylindrical portion 82 and flowing in the circumferential direction, a downward flow (downflow) of the purge gas can be easily formed in the cylindrical portion 82. That is, a downward flow can be formed in the second flow path.

In this manner, by positively purging the vicinity of the upper end (ceiling portion) of the heat generating portion 76B in which the sub-heater 76 is provided, in particular, in the gas cylinder portion 82 with the purge gas volume, the process gas can be prevented from contacting the heat generating portion 76B. The purge gas supplied from the supply port 80A is discharged through the second flow path, which is a space between the holding portion 80 and the inner wall of the cylindrical portion 82, through the exhaust hole 78A and the exhaust port 64, and exhausts the atmosphere in the heat insulating portion 70. This can suppress diffusion of the purge gas passing through the heat shield 70 into the process field a, and can suppress degradation of film formation uniformity due to dilution of the process gas in the process field a.

In the above description, the cylindrical portion 82 is included in the heat insulating portion 70 for convenience, but the region below the sub-heater 76, that is, the region of the heat insulator 74, is mainly used for heat insulation, and therefore, the region of the heat insulator 74 may be referred to as a heat insulating portion. In this case, it is also conceivable to provide the sub-heater 76 between the boat 26 and the heat shield.

The embodiments of the present invention have been specifically described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

For example, in the above embodiment, an example in which HCDS gas is used as the raw material gas is described. However, the present invention is not limited to the above manner. For example, monochlorosilane (SiH) can be used as the raw material gas in addition to HCDS gas₃Cl, abbreviation: MCS) gas, dichlorosilane (SiH)₂Cl₂For short: DCS) gas, trichlorosilane (SiHCl)₃For short: TCS) gas, tetrachlorosilane, i.e., silicon tetrachloride (SiCl)₄For short: STC) gas, octachlorotris silane (Si)₃Cl₈For short: OCTS) gas, or tris (dimethylamino) silane (Si [ N (CH) ]₃)₂]₃H, abbreviation: 3DMAS gas, tetrakis (dimethylamino) silane (Si [ N (CH) ]₃)₂]₄For short: 4DMAS gas, bis (diethylamino) silane (Si [ N (C) ]₂H₅)₂]₂H₂For short: BDEAS) gas, di-tert-butylaminosilane (SiH)₂[NH(C₄H₉)]₂For short: BTBAS) gas, or the like, and an amino (amine) silane source gas containing no halogen group. Further, monosilane (SiH) can be used as the raw material gas₄For short: MS) gas, disilane (Si)₂H₆For short: DS) gas, trisilane (Si)₃H₈For short: TS) a halogen-free inorganic silane source gas such as a gas.

In addition, for example, in the above embodiment, NH is used as the reaction gas₃Examples of gases includeThe description is carried out. However, the present invention is not limited to the above manner. For example, as a reaction gas, except NH₃As a gas, diazene (N) may be used₂H₂) Gas, hydrazine (N)₂H₄) Gas, N₃H₈A hydrogen nitride-based gas such as a gas, a gas containing the above compound, and the like. In addition, as the reaction gas, triethylamine ((C) can be used₂H₅)₃N, abbreviation: TEA gas, diethylamine ((C)₂H₅)₂NH, abbreviation: DEA) gas, monoethylamine (C)₂H₅NH₂For short: ethylamine-based gas such as MEA gas, and trimethylamine ((CH)₃)₃N, abbreviation: TMA gas, dimethylamine ((CH)₃)₂NH, abbreviation: DMA) gas, monomethylamine (CH)₃NH₂For short: MMA) gas, etc. In addition, as the reaction gas, trimethylhydrazine ((CH) can be used₃)₂N₂(CH₃) H, abbreviation: TMH) gas, and the like.

For example, in the above embodiment, HCDS gas is used as the raw material gas, and NH gas is used as the reaction gas₃An example of forming the SiN film by using a nitrogen (N) -containing gas (nitriding gas) such as gas has been described. However, the present invention is not limited to the above manner. For example, oxygen (O) is used in addition to or in addition to oxygen₂) Oxygen (O) -containing gas (oxidizing gas) such as gas, propylene (C)₃H₆) Carbon (C) -containing gas such as gas, boron trichloride (BCl)₃) The SiO film, SiON film, SiOCN film, SiOC film, SiCN film, SiBN film, SiBCN film, and the like are formed by the following film formation procedure, for example, using a boron (B) containing gas such as a gas. The order of flowing the respective gases can be appropriately changed. In the case of performing the above film formation, the film formation can be performed under the same process conditions as those of the above embodiment, and the same effects as those of the above embodiment can be obtained.

In the above embodiment, for example, an example of forming a silicon-based insulating film such as a SiN film is described. However, the present invention is not limited to the above manner. For example, the present invention can be suitably used when an oxide film containing a metal element such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), aluminum (Al), molybdenum (Mo), or tungsten (W), that is, a metal-based film, is formed on a wafer W.

For example, in the present invention, a TiN film, a TiO film, a TiON film, a TiOCN film, a TiOC film, a TiCN film, a tibbn film, a TiBCN film, a ZrN film, a ZrO film, a ZrON film, a ZrOCN film, a ZrCN film, a ZrBCN film, a HfN film, a HfON film, a HfOC film, a HfCN film, a HfBN film, a HfBCN film, a TaN film, a TaO film, a TaON film, a TaOCN film, a TaOC film, a TaCN film, a TaBN film, a TaBCN film, a NbN film, a NbO film, a NbON film, a NbOCN film, a NbOC film, a NbCN film, a NbBN film, an AlN film, an AlON film, an AlOCN film, an AlCN film, an albbn film, an AlBCN film, a MoN film, a MoO film, a mowbon film, a wobn film, WOCN film, etc. may be used as appropriate. In addition, in the case of forming a film obtained by doping (adding) another element to any one of them, for example, a TiAlN film, a TaAlN film, a TiAlC film, a TaAlC film, TiSiN, a TiSiC film, or the like, the film can be suitably used.

In the case of forming a metal-based film, for example, titanium tetrachloride (TiCl) can be used as the raw material gas₄) Gas, titanium Tetrafluoride (TiF)₄) Gas, zirconium tetrachloride (ZrCl)₄) Gas, zirconium tetrafluoride (ZrF)₄) Gas, hafnium tetrachloride (HfCl)₄) Gas, hafnium tetrafluoride (HfF)₄) Gas, tantalum pentachloride (TaCl)₅) Gas, tantalum pentafluoride (TaF)₅) Gas, niobium pentachloride (NbCl)₅) Gas, niobium pentafluoride (NbF)₅) Gas, aluminium trichloride (AlCl)₃) Gas, aluminum trifluoride (AlF)₃) Gas, molybdenum pentachloride (MoCl)₅) Gas, molybdenum pentafluoride (MoF)₅) Gas, tungsten hexachloride (WCl)₆) Gas, tungsten hexafluoride (WF)₆) An inorganic metal source gas containing a metal element and a halogen element. Further, as the raw material gas, for example, trimethylaluminum (Al (CH) may be used₃)₃For short: TMA) gas, etc., containing a metal element and carbon. As the reaction gas, the same gas as in the above embodiment can be used.

For example, a TiN film, a TiO film, a TiON film, a TiCN film, a TiAlC film, TiAlN, a TiSiN film, or the like can be formed on the wafer W by the following film formation procedure.

The order of flowing the respective gases can be appropriately changed. Even in the case of performing the above-described film formation, the film formation can be performed under the same process conditions as those of the above-described embodiment, and the same effects as those of the above-described embodiment can be obtained.

That is, the present invention can be applied to the case of forming a film containing a predetermined element such as a semiconductor element or a metal element.

In the above embodiment, an example of depositing a film on the wafer W is described. However, the present invention is not limited to the above-described manner. For example, the present invention can be suitably applied to a wafer W and a film formed on the wafer W when a process such as an oxidation process, a diffusion process, an annealing process, and an etching process is performed.

The embodiments of the present invention have been described above specifically, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention.

< preferred mode of the invention >

The embodiments of the present invention are described below in the attached form.

(attached note 1)

According to one aspect of the present invention, there is provided a substrate processing apparatus including:

a reaction tube having a process field for processing a substrate therein and a heat insulating field below the process field,

a process gas supply unit configured to supply a process gas to the substrate in the process field,

a first exhaust unit formed in the reaction tube and configured to exhaust an atmosphere in the processing region,

a purge gas supply portion that supplies a purge gas to the heat insulating region, an

A second exhaust unit formed in the reaction tube and configured to exhaust an atmosphere in the heat insulating region,

wherein the second exhaust unit is formed below the first exhaust unit.

(attached note 2)

The device described in supplementary note 1, preferably,

further, the exhaust buffer chamber is communicated with the first exhaust part and the second exhaust part.

(attached note 3)

The device according to supplementary note 1 or 2, preferably,

having a first partition part dividing the inside of the reaction tube into a plurality of spaces,

the first exhaust portion is formed of a plurality of laterally long slit-shaped openings.

(attached note 4)

The device described in supplementary note 3, preferably,

the total opening area of the first exhaust portion is larger than the opening area of the second exhaust portion.

(attached note 5)

The device according to any one of supplementary notes 1 to 4, preferably,

the reaction tube further includes a third exhaust portion formed in a flange portion formed at a lower end of the reaction tube for exhausting an atmosphere in the heat insulating region.

(attached note 6)

The device described in supplementary note 5, preferably,

the lateral width of the second exhaust portion is greater than the lateral width of the third exhaust portion.

(attached note 7)

The device according to supplementary note 5 or 6, preferably,

has an exhaust port formed in the flange portion and communicating with the exhaust buffer chamber,

the third exhaust portion communicates with the exhaust port.

(attached note 8)

The device described in supplementary note 7, preferably,

the second exhaust portion is formed at a height position at which at least a part of an opening of the second exhaust portion overlaps with an opening region of the exhaust port.

(attached note 9)

The device according to any one of supplementary notes 2 to 8, preferably,

further comprises a supply buffer chamber for accommodating the purge gas supply unit.

(attached note 10)

According to another aspect of the present invention, there is provided a reaction tube,

the reaction tube having a process chamber therein, the process chamber including a process region where a substrate is processed and an insulation region located below the process region,

the reaction tube has:

And a second exhaust unit that is formed at a position overlapping the heat insulating region in the height direction and exhausts the atmosphere in the heat insulating region.

(attached note 11)

According to still another aspect of the present invention, there is provided a method for manufacturing a semiconductor device or a method for processing a substrate, the method including:

a step of carrying the substrate into a processing region of a processing substrate in a reaction tube,

a step of supplying a process gas to the substrate in the process field, exhausting an atmosphere in the process field from a first exhaust portion formed in a reaction tube, and processing the substrate, and

and a step of supplying a purge gas to an insulating region located below the process region in the reaction tube, and exhausting an atmosphere in the insulating region from a second exhaust portion formed below the first exhaust portion to purge the insulating region.

(attached note 12)

According to still another aspect of the present invention, there is provided a program for causing a computer to execute:

and supplying a purge gas to an insulating region located below the process region in the reaction tube, and exhausting an atmosphere in the insulating region from a second exhaust portion formed below the first exhaust portion to purge the insulating region.

(attached note 13)

supplying a process gas to the substrate in the process field, and processing the substrate by exhausting an atmosphere in the process field from a first exhaust portion formed in a sidewall of the reaction tube, and a process chamber, and a process chamber

And supplying a purge gas to an insulating region located below the process region in the reaction tube, and purging the insulating region by exhausting an atmosphere in the insulating region from a second exhaust part formed in a side wall of the reaction tube at a position overlapping the insulating region in a height direction.

Description of the reference numerals

10 substrate processing apparatus

12 treatment furnace

14 heater

18 reaction tube

18A, 18B partition

19 exhaust port

24 process chamber

24A gas supply space (supply buffer chamber)

24B gas supply space (exhaust buffer chamber)

38 exhaust pipe

54. 66, 70 thermal insulation

200 controller

Claims

1. A substrate processing apparatus comprising:

A wafer boat, the wafer boat arranges and holds the plurality of substrates at predetermined intervals in the vertical direction in a state where the substrates are horizontally aligned and aligned with each other;

a heat insulation part, the heat insulation part is arranged below the wafer boat;

A reaction tube, the reaction tube is formed into a cylindrical shape with a closed upper end and an open lower end, the reaction tube has a processing chamber inside, and the processing chamber includes a processing area where the wafer boat is arranged, and the heat insulating portion is arranged the insulated area;

a flange formed on the lower end of the reaction tube so as to protrude to the outer peripheral side;

a supply buffer chamber, the supply buffer chamber is formed in a vertical direction so as to protrude outward of the side wall of the reaction tube;

an exhaust buffer chamber, the exhaust buffer chamber is formed in a vertical direction protruding outward of the side wall of the reaction tube in a manner facing the supply buffer chamber;

a first exhaust port, the first exhaust port is formed in a partition part to exhaust the atmosphere of the processing area, the partition part separates the reaction tube from the exhaust buffer chamber and constitutes the reaction a portion of the side wall of the tube;

an exhaust port in communication with the exhaust buffer chamber;

a purge gas supply that supplies a purge gas to the insulating region; and

A second exhaust port, which is formed at a position of the partition that overlaps the heat insulating area in the height direction, and discharges the atmosphere of the heat insulating area directly to the exhaust buffer chamber gas.

2 . The substrate processing apparatus according to claim 1 , wherein the heat insulating portion is formed in a cylindrical shape, and exists between the heat insulating portion and the inner wall of the reaction tube around the heat insulating portion. 3 . The purge gas can be directed to the narrow gaps of the processing zone.

3. The substrate processing apparatus of claim 2, wherein,

The substrate processing apparatus further includes:

a header having an opening at its lower end, the header supporting the flange;

a disc-shaped furnace mouth cover capable of air-tightly closing the opening of the header; and

a rotating mechanism, the rotating mechanism is arranged on the opposite side of the furnace mouth cover body and the processing chamber, the rotating mechanism rotates the wafer boat,

The said purge gas supply part is connected to the said rotation mechanism, and supplies the said purge gas from the lower part to the upper direction of the said heat insulation area.

4. The substrate processing apparatus of claim 3, wherein,

A third exhaust port is provided on the flange, the third exhaust port penetrates the flange, communicates the lower part of the processing chamber with the exhaust buffer chamber, and connects the heat insulation area to the exhaust buffer chamber. Atmosphere exhaust.

5. The substrate processing apparatus of claim 4, wherein,

The opening area of the second exhaust port is larger than the opening area of the third exhaust port.

6. The substrate processing apparatus according to any one of claims 3 to 5, wherein:

The second exhaust port is formed at a position where at least a part of the opening of the second exhaust port overlaps the opening area of the exhaust port in the height direction.

7. The substrate processing apparatus according to any one of claims 1 to 3, wherein:

The heat insulating portion is divided into a cylindrical upper heat insulating body and a cylindrical lower heat insulating body, and the upper heat insulating body is configured to be separated from the lower heat insulating body by a predetermined interval. the support part supports,

The second exhaust port is formed at a position where at least a part of the opening of the second exhaust port overlaps with a part of the predetermined interval vacated in the height direction.

8. The substrate processing apparatus according to any one of claims 3 to 5, wherein:

The first exhaust port includes a plurality of horizontally long exhaust slits provided in a range from a lower portion to an upper portion of the processing region.

9. The substrate processing apparatus of claim 7, wherein,

A partition part separates the reaction tube and the supply buffer chamber and constitutes a part of a side wall of the reaction tube, and a plurality of horizontal lengths are formed in the partition part from a lower part to an upper part of the processing region. supply slit.

10. The substrate processing apparatus according to any one of claims 3 to 5, wherein:

It also includes a nozzle, the nozzle is provided in the supply buffer chamber, and supplies a variety of processing gases and inert gases to the processing area,

On the side surface of the nozzle, at positions corresponding to the plurality of supply slits, there are formed a plurality of gas supply holes which are respectively opened so as to face the center of the reaction tube.

11. The substrate processing apparatus according to any one of claims 3 to 5, wherein:

The upper surface of the furnace mouth cover also has a sealing member and a disk-shaped protective plate, the sealing member is in contact with the lower end of the header, and the protective plate is provided in an area inward of the sealing member to protect the furnace mouth. cover.

12. The substrate processing apparatus of claim 2 or 3, wherein,

The heat insulating portion includes a plurality of plate-shaped heat insulating bodies and a cylindrical portion surrounding the heat insulating bodies,

There is also a heater between the substrate and the insulator for heating the processing area,

The purge gas supply unit supplies the purge gas into the cylindrical portion.

13. The substrate processing apparatus of claim 3, wherein,

The insulating part includes:

a receiving part, the receiving part has the shape of a circular plate with a through hole formed in the center, and is fixed on the hollow rotating shaft of the rotating mechanism;

a heat insulator, the heat insulator is formed by stacking a plurality of reflectors and a plurality of heat insulation boards;

a holding part, the holding part has a cylindrical shape with upper and lower ends open, is disposed on the upper surface of the receiving part, and holds the heat insulator;

a cylindrical portion, the cylindrical portion having a cylindrical shape with an upper end closed, disposed on the upper surface of the receiving portion, and covering the heat insulator; and

a sub-heater including a support portion penetrating the inner side of the holding portion, and a heat generating portion horizontally arranged in a space between an upper end of the support portion and an inner wall of the cylindrical portion,

The space between the inner surface of the holding portion and the outer surface of the support portion constitutes a path for supplying the purge gas.

14. The substrate processing apparatus of claim 6, wherein,

The first exhaust port is constituted by a plurality of horizontally long exhaust slits provided in the range from the lower part to the upper part of the processing area,

The upper end of the exhaust buffer chamber is closed,

The exhaust buffer chamber extends in a vertical direction and the lower end reaches the flange.

15. A method of manufacturing a semiconductor device, the method having the following steps:

A plurality of substrates are held in a wafer boat and carried into a processing area for processing the substrates in the reaction tube. The wafer boat arranges the substrates at predetermined intervals in the vertical direction in a state where the substrates are horizontally aligned and aligned with each other. be maintained;

To the substrate in the processing area, a plurality of types of processing gases are alternately supplied from nozzles provided in the supply buffer chamber, and the gases are exhausted through a first exhaust port formed in a partition between the reaction tube and the exhaust buffer chamber. The atmosphere in the processing region is evacuated to the exhaust buffer chamber, which is formed in the vertical direction so as to protrude outward from the side wall of the reaction tube to process the substrate. the exhaust buffer chamber is formed in a vertical direction so as to protrude outward of the side wall of the reaction tube so as to face the supply buffer chamber; and

A purge gas is supplied to a heat insulating area provided with a cylindrical heat insulating portion located below the processing area in the reaction tube, and the reaction tube and the heat insulating portion are separated through a second exhaust port The atmosphere in the gap is directly exhausted to the exhaust buffer chamber, thereby purging the heat insulating area, and the second exhaust port is opened in the partition part so as to face the heat insulating part .